More than 100 days after 84-year-old Nancy Guthrie vanished from her Tucson, Arizona home, investigators are now looking to bring in new tools to help find her.
A CrimeCon panel in Las Vegas revealed that federal sources are discussing bringing in technology-related tools to the investigation, but no further details were provided.
It has now been four months since Nancy Guthrie was last seen alive on February 1, with authorities pursuing hundreds of leads and tips but still not uncovering her whereabouts, identifying a suspect or confirming a motive.
The Guthrie family is still offering a $1 million reward for information, and the FBI is separately advertising a $100,000 reward.
Savannah Guthrie has spent $500,000 of her own money hiring private investigators to assist with the case, and remains committed to finding her mother.
The private search effort includes former federal agents, security professionals and specialist investigators, all of whom are working leads every day.
Investigations are also questioning the hair evidence and ransom notes, with experts pointing out that the hair was not immediately sent to the FBI lab and the ransom notes lacked urgency or proof of life.
